Carbono orgânico total, biomassa microbiana e atividade enzimática do solo de áreas agrícolas, florestais e pastagem no médio Vale do Paraíba do Sul (RJ)

Abstract

RESUMOCaracterísticas do solo, como o carbono orgânico total (COT), a biomassa microbiana e a atividade enzimática, são influenciadas por diversos fatores e têm sido apontadas como indicadores adequados de alterações provocadas por diferentes sistemas de uso e manejo do solo. O objetivo deste trabalho foi avaliar o COT, a biomassa microbiana e a atividade enzimática de um Cambissolo Háplico Tb distrófico típico de áreas agrícolas, florestais e de pastagem, no Médio Vale do Paraíba do Sul (RJ). Os sistemas avaliados foram: agricultura anual (AgAn); agricultura perene (AgP); pasto; floresta secundária em estádio inicial de sucessão (FSEI); floresta secundária em estádio médio de sucessão (FSEM); e floresta secundária em estádio avançado de sucessão (FSEA). Foram coletadas amostras de terra na camada de 0-5 cm, em duas épocas distintas (úmida e seca), e analisados o COT e as propriedades biológicas: C da biomassa microbiana -CBM; N da biomassa microbiana -NBM; respiração basal -RB; quociente metabólico -qCO 2 ; quociente microbiano -qMIC; e atividade das enzimas arilsulfatase, β β β β β-glicosidase e fosfatase ácida. As áreas agrícolas apresentaram redução no COT e nas propriedades

Biological Properties and Organic Matter Dynamics of Soil in Pasture and Natural Regeneration Areas in the Atlantic Forest Biome

“…Similar MBCs between native forest and pasture areas were also found in studies carried out in São Paulo (Marchiori Júnior and Mello, 1999) and Rio de Janeiro (Silva et al, 2012a).…”

“…These practices can affect ecosystem equilibrium and the chemical, physical, and biological properties of soil, which can be considered indicators of environmental degradation and recovery (Machado et al, 2010;Silva et al, 2012a;Guareschi et al, 2014).…”

Reforestation of a Degraded Area with Eucalyptus and Sesbania: Microbial Activity and Chemical Soil Properties

“…Although there was no significant difference in FDA between the dry and rainy seasons for the 50S:50E stands, there was a tendency toward higher values of total enzyme activity in the dry season, in which the highest C and N levels were observed. Silva et al (2012) found high correlations between the activity of different enzymes (β-glucosidase, arylsulfatase, and acid phosphatase) and C in soils of forest systems at different stages of succession. The higher FDA activity in the 100E plantation and respiration in the 100S plantation in the dry season may be related to greater litter deposition rates at that time, which can stimulate microbial activity.…”

“…The authors claim that FDA activity represents the heterotrophic potential of Rev Bras Cienc Solo 2017;41:e0160239 soils because it represents the activity of enzyme groups that decompose organic matter (Dick et al, 1996). Other studies (Evangelista et al, 2012;Silva et al, 2012) have shown that the activity of several enzymes is influenced by the levels of organic matter in soils.…”

“…The higher contents of C and N in the soil during the rainy season compared to the dry season in the 100S plantations may be associated with higher total microbial activity (FDA) in the soil at that time, which can increase litter decomposition rates and the incorporation of C and N into the soil (Batista et al, 2008;Silva et al, 2012). The same pattern may help explain the higher content of P during the dry season for the 100E planting, when there was greater FDA activity.…”